For me:

4 Westinghouse OV-25s
GE Post Top.

That's it lol.

I recently discovered a string of M-250A split-doors on a access road along I-71 in Columbus

There's some 250w MV bracket fixtures and 175w MV NEMA's as rental lights. Xcel says in the rental light form that mercury and HPS lights will be maintained and kept unless the ballast fails. I know of some really dim rental lights but they aren't on my property so I'm not going to report them.
There's also a few 400w MV cobraheads tucked away in some parts of Minneapolis. Apparently they are city owned and should be safe from LED replacement. They are still maintained, too.

I remember two 400w MV Revere 2600s at the United States Post Office in my city but sadly when the lamps went, they also went. They got replaced by LED waffles. There's another with 8ft turrets that got converted to 4x F32T8 and a 400w MV LM Unistyle that still works but has a dim lamp.

There is more mercury fixtures in service in my area than i could count on my fingers and toes.

First, great thread!  

In my neighborhood, there a GE P17 post top which is used most nights. There also two earlier GE post tops but not sure if they still used. Plus a NEMA head rental that's still bright. And a couple of McGraw Handyman fixtures that work every night at a few houses, plus one on Pizza Hut and two at an AT&T store.

Downtown there are some GE 101SA and some AEL L series NEMAs, and a couple of Westy Viscount NEMAs. There are two Westy OV-25 2nd gens that I know of and a 1964 GE M-400 that all still work well. And finally some American Electric Series 25s and two early 60s AE 15-000. Oh and another neighborhood has two Westinghouse RMA NEMA fixtures, both are pretty dim and one is missing its refractor. Also there are a couple of GE M-250R2s that are really dimmed out at another neighborhood. Plus some houses have some MV yardblasters and I seen one on a church, all are bright, one runs 24/7.

There's a good number of mostly privately owned mercury fixtures left around the GTA even though streetlighting is pretty much all HPS, MH or LED since the early 90s.

Around here I see some older office buildings and malls that still have 100-175w recessed mercury vapour cans over the entrances and sometimes in the lobby/corridors. There's a subway station that has 175w mercury recessed sqaures with reflector lamps on the concourse level. Ironically I think all the fluorescents there got T8 LED tubes. Some of the older subway stations also have 175-400w Unistyles, M250s, etc lighting the entrances and bus loop areas. Finally there's a few post tops in some parks that I swear are running 175w MV instead of MH.

Los Angeles and a number of surrounding cities still have a good number of mercury vapor street lights, and they are still maintained. Mostly cobraheads, but they also come in decorative lights. Here, where I live, two freeway overpasses have mercury soffit lights underneath. That's it, aside from parking lots.

For clear mercury-vapor? Mainly NEMA heads, usually in residential zones but rarely in a commercial area. For color-corrected mercury vapor, there are many more, including some NEMA heads. A few modern fixtures, surprisingly use mercury-vapor ( color corrected ).